Communication system



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COMMUNICATION SYSTEM r Original Filed Aug. 17, 1940 11 Sheets-Shae; l

F I l v SEND-P56275 D/J'TK/EUIUR WISE/V81 Y ATTORNEY.

Qct. 6, 1942. H. J. NlCHOLS ETAL 2,297,794 COMMUNICATION SYSTEM OriginalFiled Aug. 17, 1940 ll Sheets-Sheet 2 ATTORNEY.

Oct. 6, 1942.

H. J. NICHOLS ETAL v COMMUNICATION SYSTEM Original Filed Aug. 1'7, 1940AII MP-i I III I IH- cum kw Oct. 6, 1942-" H. J. NICHOLS ETALCOMMUNICATION SYSTEM Original Filed Aug. 17, 1940 ll Sheets-Sheet 4INVENTORS HAP? Y J NICHOLS BY l/E/VR Y L 7/!01671'0! QMQ EE Oct. 6,1942. J. NICHOLS ETAL COMMUNICATION SYSTEM I Original Filed Aug. 1'7,1940 ll Sheets-Sheet 5 ATTQRNEY.

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- commumcnmu s sma Original Filed Aug. 17, 1940 11 Sheets-Sheet 6 f/;L\\ v ATTORNEY H. J. NICHOLS ETAL 2,297,794

COMMUNICATION SYSTEM Original Filed Aug. 17, 1940 ll Sheets-Sheet '7IIEWAY z. mozs mar .giqmgav.

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comuumca'rion SYSTEM Original Filed Aug. 17, 1940 11 Sheets-Sheet 8ATi'ORNIY.

Oct. 6, 1942. H. J. NICHOLS ETAL COMMUNICATION SYS TEM Original Fi ledAu 17, 1940 ll Sheets-Sheet 9 H. J/NICHOLS ET AL ,2 7,794

COMMUNICATION SYSTEM Original Filed Aug. 17, 1940 ll Sheets-Sheet l0III] IN VEN TORS H/MAY ZN/679015 HEM? Y L. THOLSTAUP ATTORNEY.

1942- H. J. NICHOLS ETAL 2,297,794

COMMUNICATION SYSTEM Original Filed Aug. 17, 1940 ll Sheets-Sheet 11NVENTORS ATTORNEY.

Patented Oct. 6, 1942 UNITED STATES PATENT OFFICE COMMUNICATION SYSTEMOriginal application August 17, 1940, Serial No. 353,113. Divided andthis application June 14, 1941, Serial No. 398,068

6 Claims.

The present invention is a division of the copending application ofHarry J. Nichols and Henry L. Tholstrup, Serial No. 353,113, filedAugust 17, 1940, which relates to interoffice or interstationcommunication systems and more particularly to communication systems forinterconnecting separate typewriters, of a certain standardconstruction, modified to conform to a telegraphic keyboard wherein theoperation of any one typewriter in a normal manner, can be isolated, atwill, from the operation of the system to permit ordinary individualoperation of the respective typewriters or, on the other hand, operationof one typewriter in the normal manner [can be utilized to locallyproduce a copy, at a ;SBI1C1iI1g station, of the intelligence to betrans- ;mitted, and to simultaneously operate a second or receivingsimilar typewriter or a plurality of such receiving typewriters atremote points. In like :manner, each of the plurality of receivingtypewriters can be utilized, when desired, as sending typewriters, andmeans are provided for break- :in by a receive station, so that thedirection of transmission can be reversed when necessary or (desired.

In devices of the prior art wherein interoflice messages have beentransmitted, special machines which are not the usual standard equipmentof business offices have been employed. There have :also been previouslyprovided, electrical interconnecting systems for standard typewriters,but such systems have generally required an extensive rebuilding of themechanical structure of the typewriter itself, to adapt it to such asystem.

Accordingly, one of the objects of the present invention is to providenovel means used for interconnecting and operating two or more standardOffice equipment typewriters, such as the well known Electromatictypewriter, modified to conform to a telegraphic keyboard so that suchan instrument is utilized, merely with parts of the original machineomitted and with very ilttle additional equipment, in an interofficecommunication system, to produce speedy and accurate transmission andreception of messages and the device is so constructed that a great partof the additional equipment is incorporated within the ambit of thetypewriter frame.

A further object is to provide a system of communication forinterconnecting at least two typewriters comprising means controlled byeach depressed key of the keyboard for setting up, in a simple anddirect manner, a code combination of signal impulses, representative ofthe function or .character represented by the depressed key andincluding start and stop signal impulses, said code combinationcomprising a plurality of electrical impulses of identicalcharacteristics and of equal duration, a single signal channelinterconnecting the typewriters, means for transmitting selectively andsequentially over said channel, the individual impulses or elements of asignal representing a particular function or character, and a novelselector comprising a mechanical translator whose elements arepositioned selectively in accordance with the individual elements of thecode combination to select one key bar only, corresponding to the keydepressed at the sending station, which key bar is operated by a seekerlever, released by a print bar controlled by a timed local impulse,whereby the depression of a chosen character key of such a standardtypewriter at one station produces typing locally and also produces thetyping of the selected character at a remote station by means of asimilar typewriter.

Still another object is to provide a' system of interoffice orinterstation communication including at least a pair of typewriters atdifferent stations, each having a modified keyboard, means controlled bya selected character key for producing a characteristic combination ofsignal code elements, an electrical connection between the respectivetypewriters comprising one signal channel over which the code signalelements of said character are sequentially transmitted, startstop,send-receive distributor means for sending or receiving, respectively,at each station, and in synchronism, the code elements comprising acharacteristic signal, and a novel selector comprising mechanicaltranslator means controlled by received code elements for translatingthe same and selectively releasing a seeker lever to operate that keybar only, which corresponds to the key depressed at the sending station.

Still another object is toprovide a novel selector comprising a novelmechanical translator and operating means therefor.

Other objects of the invention will be pointed out in the followingdescription and claims and illustrated in the accompanying drawings,which disclose by way of example, the principle of the invention and thebest mode which has been contemplated of applying that principle.

In the drawings:

Fig. 1 is a diagrammatic view illustrating teleprinting devices such astypewriters suitable for ordinary oflice work and also utilized in theproduction of code signal permutations representativ of a character andalso controllable by remotely originating signals to type a character,and means for electrically interconnecting a pair of such devices by aminimum number of signal channels for signal transmission therebetween,the translator and permutation units being contained within theframework of the typewriter.

Fig. 2 is a diagrammatic view, in skeleton outline only, illustratingfundamentally how the operation, at the send station, of a character keyproduces a code permutation ofsignal components representative of theparticular char acter, which components, by means not shown in Fig. 2,in turn are relayed, in seriatim, to the signal channel, by asend-receive distributor assembly, and also illustrating fundamentallyhow a corresponding key bar is operated by a seeker lever correspondingto a characteristic signal received from a remote station, after saidsignal has been translated, to thereby select the corresponding seekerlever.

Fig. 3 is a. schematic diagram, illustrating in skeleton outline theessential elements of a complete communication system including separatetransmitting and receiving stations, respectively, with the start-stopclutches in the preliminary stop position and illustrating the signalchannel between the stations.

Fig. 4 is a schematic diagram, generally like Fig. 3, but illustratingin greater detail circuits and elements of the transmitting andreceiving mechanisms and including the circuits for break-in andkeyboard lock-out or latching.

Fig. 5 is a fragmentary perspective view illustrating diagrammaticallythe mechanism for producing keyboard lock-out or latching.

Fig. 6 is a, diagrammatic View illustrating the means for and manner ofoperation of the contacts comprising a transmitting or a receivingdistributor. and the ranging mechanism for adjusting the timing of thedistributor.

Fig. 6a is an end. view of the device of Fig. 6.

Fig. 7 is a perspective View illustrating the translator unit, theseeker levers and the mechanism for operating the print or drop bar.

Fig. 8 is a side elevation, illustrating in more detail, the mechanismfor operating the print or drop bar.

Fig. 9 is a fragmentary side view, partly in section, of the device ofFig. 8.

Fig. 9a is a detailed view of the piston element of Figs. 8 and 9.

Fig. 9b is a detailed view of the combined pin and pivot element ofFigs. 8 and 9.

Fig. 10 is a schematic view illustrating fundamentally the manner ofoperation of the actuating mechanism for the print or drop bar under thecontrol of a timed local impulse.

Fig. 11 is a plan View of the translator unit, in part, illustratingschematically the latching of a permutation slide bar by a translatormagnet latch.

Fig. 12 is a front view of the device of Fig. 11 and illustratingfurther details of the translator unit.

Fig. 13 is a fragmentary sectional view illustrating, the rollerslocated between the permutacion bars.

Fig. 14 is a plan view of the translator unit, in part, illustratingschematically the release of a permutation slide bar by a translatormagnet.

Fig. l5.is a front view of the device of Fig. 14, and also illustratingschematically the restore magnet and its armature for resetting thepermutation slide bars.

part of a circuit associated with a translator magnet.

Fig. 17 is a side elevation, in section, of one form of novelstart-stop, single revolution clutch mechanism and including thetransmitting and receiving cams, the latch contact operating cam, andthe circuit breaker cam.

Fig. 18 is a perspective view illustrating the construction of thespider of the clutch mechanism.

Fig. 19 is a partial sectional View, illustrating the position of theclutch driving pins, with relation to the spider and a driving cup, whenthe clutch is disengaged.

Fig. 20 is a partial sectional View illustrating the clutch controllingdisk mounted on the spider, and the manner in which the controlling diskactuates the clutch driving pins to the disengaged position of Fig. 19.

Fig. 21 is a view similar to Fig. 20 but with the controlling diskadvancing the driving pins to their engaged position.

Fig. 22 is a view similar to Fig. 19 but with the driving pins in theengaged or locked position of Fig. 21.

Fig. 23 is a sectional view illustrating the latch contact operatingcam, the controlling disk and the accelerating spring in position.

Fig. 24 is a sectional view of the latch contact operating cam hub andthe clutch spider, and the detent pawl for holding the parts in stoppedposition.

Fig. 25 is a diagrammatic view illustrating the coaction of thestart-stop magnet, start-stop magnet armature and the stop pin of theclutch controlling disk.

Figs. 25a, 25b and 250 are diagrammatic views illustrating the relativepositions of the stop pin and start-stop armature under differentoperating conditions.

Fig. 26 is a perspective view illustrating the shift and carriage-returnoperating and signaling mechanism.

Referring to the drawings wherein like reference characters refer tolike parts throughout the several views and more particularly to Fig. 1,the invention is illustrated in the present example, as applied to apair of modified Electromatic typewriters A and B at the sending stationA and the receiving station B, respectively, but it is to be expresslyunderstood that any type of standard ofiice typewriter with a modifiedkeyboard can be utilized in the. novel combination of the presentinvention and that any number of typewriters can be so interconnected.

Typewriter A. comprises an Electromatic typewriter provided with amodified or telegraphic keyboard wherein the typebars are poweractuatedin a well. known manner, upon depression of a chosen characterkey and wherein a blank key SRKI, controls a send-receive relay (Fig. 4)as will be described in detail later.

Upon depression of any chosen character key, the character is typed onthe record sheet 5%] at station A and the permutation unit (Fig. 2) isconditioned; as will be described later, so that an electrical signalisproduced, composed of a predetermined permutation of similarelectrical components, which components, by means of a send-receive.distributor assembly, diagrammatically represented in Fig. 1, includinga novel start-stop, single revolution clutch mechanism and'send-receiveand line relays; are transmitted sequentially over a signal channelrepresented as a line to the-typewriter. B at the receive station.

It is to be specifically understood that any type of signal channel maybe utilized. The respective signal components, when received by theend-receive distributor assembly at the receive station B, sequentiallycondition the respective translator magnets (Fig. 11) of a noveltranslator mechanism, as will be explained in detail later, whereby thepermutation slide bars of the translator are operated to align theirrespective slots with a certain seeker lever (Fig. 7), in accord ancewith the particular signal code permutation received. All the seekerlevers are each connected to a key bar, respectively, (Fig. 2), and thekey bar at a receive station controlled by the chosen seeker levercorresponds to the character key depressed at the send station.

Alignment of the slots of the slide bars as described above, by theselecting code signal elements of the signal, conditions one selectedseeker lever for operation, and upon reception of the seventh or printpulse of the complete signal, the print magnet PM (Figs. 4 and isenergized to depress the print or drop bar as described in detail laterand the selected seeker lever is actuated by its associated spring tooperate the corresponding character key at the receive station, so thatthe same character is typed on the record sheet (Fig. 1) at both thesend and receive stations. Similarly, any of the letters can be typedand any function can be performed, so that any message can be typed atstation A and signals set up at station A, which when transmitted tostation B, will produce typing of the same message on the machine atthat station.

When the operator at station A wishes to send a message to station B, tobe simultaneously typed upon both machines, the operator at station A,depresses the blank key SRKI, thereby conditioning the machine atstation A for sending, station B being normally in receive condition,all as will be described in detail later. Warning and other signalingmeans may be provided between stations, in a manner well known in theart but such warning and signaling means do not constitute any part ofthe present invention.

Referring specifically to Fig. 2, there is illustrated, in skeletonoutline only, the mechanism and circuits for the operation of a chosencharacter key at station A with the consequent mechanical typing of theselected character at station A and the setting up of means forproducing a signal, representative of the character, whereby such asignal may be transmitted to station B to produce typing of thecorresponding character at said station. The operation of thesendconditioned machine to produce a signal for remote operation of areceive-conditioned machine is as follows: Upon depression of a chosenchar acter key 5i, the key bar 52 is oscillated about its pivot pin 53against the force of return spring 54 to move an extension arm 55downwardly. Upon such downward movement, the bifurcated lower end of arm55 engages a pin 56 on arm 57 integral with the stop lever 53, tothereby rotate stop lever 58 counterclockwise about its pivot 59. Thisrotation disengages the channel shaped lug 60 of stop lever 58 from theright hand one of a pair of detents 6|, on cam 62. An impeller arm 63,in contact with an impeller lug 64 on cam 62 is constantly urged in aclockwise direction by means of a spring 65 and upon the disengagementof the channel shaped lug 60 of the stop lever from a detent 6| of thecam, the impeller arm 63, by means of its contact with impeller lug 64,rotates the cam 62, slightly in a clockwise direction, until the camengages the constantly rotating power roller 66 which is rotated aboutthe stationary shaft 67 by means of the typewriter motor (not shown) ina manner well known in the art. The cam 62 by means of its engagementwith power roller 66 is thereupon rotated a full half revolutionclockwise, until the other, detent 6|, of the pair of detents on cam 62,engages the channel shaped lug 60 of stop lever 58, in a well knownmanner. Cam 62 is pivotally mounted by its axis 68 upon an arm 69 of abellcrank 10 which in turn is mounted for oscillation about a pivot II,and upon such rotation of cam 62, its eccentric contour causes a lateralmovement of the cam axis 68 to thereby oscillate bellcrank 10 in acounterclockwise direction. Such oscillation causes a downward movementof the arm 69a. of bell-crank In to thereby pull down a link I2, torotate a bell-crank 13 against the force of spring '14 to actuate link15 to oscillate bell-crank T6 to in turn actuate the type bar TI tostrike one of the type characters 78 against the record 56 (Fig. 1), ina manner well known in the art.

Also, upon rotation of cam 62 and consequent lateral movement of the camaxis 68, a roller 19 carried on the lower end of arm 69, is movedlaterally to the right, as viewed in Fig. 2. Roller 19 is in engagementwith a shoulder 86s on a permutation slider 86 mounted on suitableslotted guide bars 8| secured to the frame (not shown) of a typewriterunit. Each slider is provided with spaced studs 82 extending outwardlyand alternately from one side and the other of the slider and such studsare carried on both the top and bottom horizontal bars 801i and 8%,respectively, of the slider member. Rotatably mounted on each of aplurality of code rockshafts 83, and alternately on opposite sides ofthe sliders are the diagrammatically represented rockshaft actuatingclips 84 which may be of the type as disclosed in the copendingapplication of Harry J. Nichols, Serial No. 353,114 filed August 17,1940. These clips 84 are removably attached to the rockshafts, asdescribed in said copending application, the relative number anddisposition of the clips in the assembly for each slider being dependentupon the particular code value of the character whose key controls therespective slider member. Therefore, upon depression of any chosencharacter key, the respective code rockshafts 83, to which the clips areattached, will be rotated, as described in said application, and in sucha direction that the particular code permutation representing thecharacter, will be set up by the respective permutation switches. It isto be particularly noted, that the universal bail rockshaft 83UB isalways actuated by means of its clip 84UB to move one out of a pair ofits controlled switch arms comprising the universal bail switch,momentarily out of engagement, to thereby produce a spacing condition onthe signal channel, this rockshaft being diagrammatically illustrated asspring biased by means of a coil spring 85 acting through its associatedclip 84UB so that the rockshaft and slider are returned to theiroriginal positions upon completion of the half revolution of cam 62.

Upon the above described lateral movement of the cam axis, the roller 19moves slider 30 to the right, as viewed in Fig. 2, against the springbias efiect of spring acting through clip {HUB and its cooperating stud,whereby the studs carried by the slider actuate the associated clips androtate the universal bail rockshaft SSU-B and such code rockshafts 83,as is required to set up the signal. Such actuation of the clips rotatesthe associated rockshafts to actuate the diagrammatically representedswitch operating elements 86133 and 85 to thereby permit the associatedspring switch arm S-lUX of the universal bail rockshaft to move out ofcontact with its associated switch arm BlUXa. and into engagement withswitch arm B'FUXb and to force certain of the associated spring switcharms or tongues 81 of the code rockshafts selectively into engagementwith the associated switch arms 81a, dependent upon the direction ofrotation of the code rockshafts, respectively. It is to beparticularlynoted, that all code permutation signal settings are differentiallyproduced and only those rockshafts are actuated which require a changefrom the setting for the previously typed character. If the same letteris typed twice in succession, the corresponding slider is twiceactuated, but only the universal bail rockshaft is rotated, the secondtime, since the remaining rockshafts are retained in their previouslyset position by the diagrammatically represented associated detent pin85d, spring pressed, by spring tits, into engagement with a notch 8611,in the operating element, as described in detail in said copendingapplication. Thus, such permutation switch elements 870. and 81 as aremoved into engagement, close a circuit from the positive side of a D. C.source Bl, as illustrated diagrammatically in Fig. 2, and the universalbail on the other hand opens the circuit from the positive side of thesame source by separation of its pair of contacts BIUX and STUXa, inseries between the positive side of said source and the distributorassembly. Contacts 8lUX and BTUXb are simultaneously moved intoengagement, to momentarily energize a latching circuit, as described indetail later.

The particular permutation of switches closed, will thereby supplypositive potential to the sendreceive distributor assembly; includingthe novel start-stop, single revolution clutch mechanism, send-receiverelay and line relay, diagrammatically illustrated in Fig. 2 as theSend-Receive Distributor Assembly; which, in turn, at the proper timeand in proper sequence, Will transmit the set-up code permutation ofsignal components, through the signal channel represented by the line,to the send-receive distributor assembly at the receive station, in amanner to be described in detail later. Upon completion of a full halfrevolution of the cam 62, the universal bail rockshaft 83UB is returnedto its normal position by spring 85 thereby forcing contacts iilUX andB'IUXb apart and producing closure of contacts B'IUX and BTUXa, but thecode rockshafts 83 are retained in their actuated positions by thecoacting detent pins, until depression of another character key bar. Itis seen, therefore, that in a simple and direct manner, a standardoffice typewriter, such as the Electromatic typewriter, modified asstated above, can be utilized, to locally type a character and to set upa code signal having a desired permutation of components, characteristicof the selected character, which signal may be transmitted over thesignal channel represented by the line, by the novel means now to bedescribed and which may be utilized at a remote typewriter to type thesame character.

The novel communication system comprising the present invention consistsof the permutation means as just briefly described, at each station, forsetting up a code signal representative of a character to be remotelytyped, a sendreceive distributor assembly, comprising in addition to asend-receive relay and a line relay, novel distributor mechanism, and anovel startstop, single revolution clutch mechanism controlled by theline relay to in turn control the operation of the distributor mechanismat the same station. The code signal set up by the permutation unit, issequentially transmitted by the sending distributor to maintainsynchrcnism between the distributor mechanisms at the local station andat the remote station and to produce typing of the desired character orperformance of the desired function, the remote distributor mechanismcontrolling novel mechanical translator means, set in accordance withthe signal elements received to thereby operate that key bar only,corresponding to the character key depressed at the sending station.

A general description coordinated by reference to the respective figuresof the drawings, will first be given, of the essential elements of acomplete communication system and then a detailed description of thesending or transmitting mechanism and circuits and of the receivingmechanism and circuits, including a detailed description of therespective component elements of these mechanisms and circuits will begiven, which will be followed by a detailed description of the operationof the complete system including transmission, reception, break-in,lock-out and other communication functions.

GENERAL DESCRIPTION A plurality of typewriters, such as the machine atstation A and the machine at station B (Fig. l) with their respectiveassociated electrical elements, a send-receive distributor assemblyincluding start-stop mechanism and various control elements areinterconnected to comprise the novel teleprinting communication system.The system operates on the start-stop, Baudot 5- unit code principle,and by means of associated circuits and mechanisms, two-way transmissionof messages over a single channel is provided.

A permutation mechanism, generally as shown and described in detail insaid copending application, and controlled in the manner asdiagrammatically illustrated in Fig. 2, is utilized to produce the startsignal by opening the line circuit, to set up a code signal of separatesignal components, characteristic of the character represented by achosen depressed key, and to produce a stop signal. The particularpermutation switch elements which are placed in a closed circuitrelation by the permutation mechanism close a circuit up to theirassociated distributor contacts, as illustrated in Figs. 3 and 4, whichcontacts are sequentially controlled upon rotation of the start-stopclutch, by the transmitting distributor cam, which is driven by thestart-stop clutch along with the receive cam, the control of saidcontacts being conventionally illustrated only, in Figs. 3 and 4.

Upon depression of a chosen character key to thereby locally type thecharacter and to simultaneously set up the code signal representative ofthat character, two of the universal bail contacts are operated to openthe line circuit and thereby release the novel start-stop clutchmechanism of Fig. 17 whereby it is rotated one complete revolution,only, and the selecting code signal permutation, as set up by thepermutation unit, is sequentially transmitted to the line by means ofthe sending distributor unit and the send-receive relay, asdiagrammatically illustrated in Figs. 3 and 4. The line signal elementsreceived at station B, operate a line relay to sequentially controllocal circuits to the respective contacts of the distributor unit oftypewriter B (Fig. 1) as this distributor rotates to therebysequentially and selectively energize the translator magnets (Fig. 4) ofthe novel translator mechanism of Figs. 11, 12, 13, 14 and 15, whichmagnets thereby selectively set the permutation slide bars of thetranslator so that the one seeker lever (Fig. 7), and the associated keylever only which corresponds to the chosen character is operated (Fig.2) upon depression of the print bar at station B (Figs. 2, 8 and 10) tothereby produce remote typing of the chosen character.

Transmitting mechanism The transmitting mechanism comprises thepermutation unit of the above mentioned copending application which iscontrolled by the key bars of the transmitting typewriter, to controlcircuits leading to contacts controlled by the transmitting cam of thedistributor mechanism. The circuits, closed by the transmittingdistributor cam, transmit code elements of the signal to a send-receiverelay at the send station, which relay controls the transmission of thesignal elements through a line relay at the sending station and to aline relay at the receiving station. The line relay at the sendingstation, controls the operation of a novel start-stop single revolutionclutch mechanism which, in turn, controls the operation of thedistributor mechanism. The construction of the permutation unit is asdescribed in detail in said copending application.

The construction of the transmitting distributor unit and ranging deviceof the send-receive mechanism, the start-stop single revolution clutchmechanism, the shift and carriage-return mechanisms and the keyboardlock-out or speed lock means will now be described in detail.

Referring to Fig. 6, there is illustrated therein the construction andassembly of a novel transmitting or receiving distributor including anovel ranging device as shown and described in applicants copendingapplication Serial No. 398,069 fined June 14, 1941. This distributor isdiagrammatically illustrated as separate from the typewriter in Fig. 1,but in actual construction it may be fastened to the back of thetypewriter to produce a compact unit.

A transmission cam TC is loosely mounted for rotation about the shaft 88(Fig. 17) along with a similar receive cam RC and the other elements asshown in Fig. 17, the receive cam and other elements being omitted inFig. 6 to clarify the illustration. Transmission cam TC controls aplurality of movable contacts or switch arms of the switches Tl, T2, T3,T4. and T5 cooperating with the permutation switches PI, P2, P3, P4 andP5 (Fig. 3) and each switch including at least a pair of switch arms aand b. The switches T|-T6 are in series between the permutation unitswitches and the send-receive relay, as diagrammatically illustratedonly, in Fig. 3, and thereby control the circuits leading from therespective permutation switches to the line. Cam TC also controls theswitch T6 shown as comprising a pair of switches operated simultaneouslyby means of the web TSa interconnecting the movable blades 0. of the twoswitches.

Referring to Figs. 6 and 6a the horizontal shaft 88 is transverselyjournaled in ball bearings 89 (only one being shown) forced intosuitable recesses 99 bored in the end of a spider 9|, rotatably mountedin the distributor end plate 92 of the distributor mechanism. The shaft88 is driven by motor means (not shown) to produce rotation of a novelstart-stop single revolution clutch mechanism 94 (Fig. 1'7), asdescribed later, under the control of one of the start-stop magnets SSMor SSMZ diagrammatically illustrated in Figs. 3 and 4.

The send or transmitting cam TC (Figs 6 and 17) is attached to a spiderof the clutch, as described later, for rotation therewith. Upon rorationof the start-stop clutch, the cam CT sequentially closes the a contactsof switches Ti to T6, inclusive (Fig; 6), against the cooperating I)contact respectively to thereby transmit to the line, the elements of aparticular code signal, as set by the permutation switches Pl to P5,inclusive (Fig. 3), each comprising the pair of contacts 81 and 810., asdescribed above, and to transmit a stop or marking line signal, asdescribed later. The contacts comprising the switches, each comprises aspring stack-up, as illustrated in Fig. 6 mounted on the spider 9| anddistributed about the circumference thereof, whereby, upon rotativeadjustment of the spider, as will now be described, the particulartiming of the closure of the contacts of the respective switches TI toT5, inclusive, by cam TC, may be adjusted.

The novel ranging device comprises the spider 9| mounted for rotativeadjustment about the shaft 88 by means of the spider adjusting plate 98attached to the spider by screws 98a, and including a slot 985 intowhich projects the adjustable thumb screw 99 for locking the spider inany desired adjusted position, the relative position being indicated bythe index pointer 98p, carried by and movable with the plate 98, andcooperating with the index plate 98b mounted on the distributor endplate. By loosening the thumb screw 99, the spider adjusting plate 98may be rotatively advanced or retarded, which in turn, advances orretards the time of closure, by cam TC, of the respective switches TI toT6, inclusive, carried by spider 9|. In this manner any shift in phaseof the line signal elements may be compensated.

The details of the novel start-stop and single revolution clutchmechanism 94 as shown and described in applicants copending applicationSerial No. 398,070 filed June 14, 1941 are diagrammatically indicatedonly in Figs. 3 and '4 and are illustrated in Figs. 17 to 23, inclusive.This clutch mechanism comprises generally an overriding roller typeclutch in which six small pins or rollers I99 coact with a spider I01and a pair of driver cups I92 and are engaged by means of a wedge actionto produce a positive drive. After the clutch has been engaged, itcontinues to rotate, locked in step with the shaft 88 by means of cupsI02, until the pawl a, for example, of stop arm 95 engages the stop pin96. The engagement of the stop pin and pawl arrests the motion of acontroller disk 91 to which the pin is attached while the energy of theother parts of the clutch causes the clutch to rotate through a smallangle which disengages the rollers I00 and thus releases the clutch.

Referring to Fig. 17, the complete clutch mechanism 94 is illustrated ascomprising the pair of driver cups I02 fastened to shaft 88 by meanssuch as set screws I-82s. Each cup comprises a cylindrical member, boredto fit the shaft 88 and provided with a counterbored portion I82cbturned concentric with shaft 88, the interior surface of thecounterbores constituting the drive surfaces of the clutch. Locatedbetween the pair of driver cups is the spider I8I (Fig. 18) mounted onand in loose contact with the shaft 88 and extending at its ends intothe interior of the counterbored portions of the cups. The rollers I08are mounted in axially extending slots or grooves IElIs (Fig. 18) formedin the outer periphery of the spider and the ends of the rollers are sopositioned as to contact the interior surfaces of the respectivecounterbores IIlZcb of the respective cups when the clutch is engaged.As is seen in Figs. 18 and 19, the slots HHS are formed eccentricallywith respect to the shaft 88 so that motion of the rollers I80 along thebottom of the slots or grooves, moves the rollers further from thecenter line of the shaft or closer thereto in accordance with thedirection of motion, so that the rollers are either thereby engaged ordisengaged from the driver cups I82. The driving rollers we are jointlycontrolled by an interiorly toothed controller disk or ring 81 (Fig. 20)which ring is rotatably mounted in a radially extending groove IGI g(Fig. 18) formed in the spider IOI and is provided with a torque springI03 (Fig. 23) having one end inserted into an axially extending opening91a in the controller ring 91 and the other end inserted into an axiallyextending opening I84a in the latch contact operating cam I84. Thespring I83, upon release of the controller ring 91, tends to rotate thecontroller ring so that the rollers I are urged towards the engagingposition (Fig. 22). The spider IBI is in frictional engagement with afiber pad ms (Fig. 17) at each end thereof which in turn is urged intoengagement with the rollers by a cup-shaped spring washer I 86 hearingon the bottom of the counterbores I02cb of the cups 102, respectively,so that a force is always exerted upon the rollers by the rotation ofthe driver cups to aid in positioning the pins in the engaged position.By adjustment of the position of the cups on the shaft 88, thefrictional force on the spider may be varied. A notch or axiallyextending slot I8! (Figs. 6 and 18) is formed in the outer edge of oneof the radially extending members I Q Ir of the spider and a driving keyI08 (Figs. 6 and 24) fastens the transmitting cam TC, latch contactoperating cam I04, (Fig. 1'7), circuit breaker cam I89 and receive camEC to the spider IOI for rotation therewith upon release of thecontroller ring 97 and engagement of the clutch.

As illustrated in Figs. and 21, the controller ring is provided with astop pin 96 cooperating with the pawls 95a and 951) on the arm 95 (Fig.25) controlled by the armature SSMA of the start-stop magnet SSM.Engagement of the pin 95 with either of the pawl 95a or 951), holds thecontroller ring 91 in position, against the force of the torque exertingspring I83, so that the rollers 10!] are held, out of the interlockingengagement, between the rollers, the driver cups and the spider. Thiscondition is illustrated in Figs. 19 and 20, the stop arm 95 beingschematically illustrated as engaging the stop pin 95. The teeth 912?(Fig. 20) of the controller ring 91 hold the rollers wt in the position,as shown in Fig. 19, so that the rollers are located in the deepest partof the slots Ill-I s of the spider and the rollers are therefore out ofengagement with the peripheries of counterbores 120b, respectively. Uponrelease of the stop pin 96, as illustrated diagrammatically in Fig. 21,the controller ring 97 is rotated by spring I 83. Simultaneously, thefriction due to washer I (Fig. 1'7) and cup shaped spring washer I08tends to rotate the spider IOI in the direction of rotation of theclutch.

In order to obtain positive and rapid engagement of the driving pins, bythe ring or controller disk 91, to lock the driving cups .to the spider,the controller ring not only must be accelerated by the acceleratingspring I93, as just described, but the spider must be held stationary inthe meantime. As is seen in Fig. 24, the hub IMa of cam I04 is providedwith a V-notch IIGb into which projects the V-shaped end Illla of thedetent lever -I I8. Since the spider Isl is connected to cam I84 by keyI08 (Fig. 24) the lever III) holds the spider stationary when the clutchis disengaged. Therefore, although the friction of members I05 and H15tend to rotate the spider, as above stated, the detent lever holds thespider against such immediate rotation. The spring I83, therefore, snapsthe ring 91 into rotation and the ring or controller disk teeth 91fquickly assume the position, as shown in Fig. 22, to thereby move thepins I68 into the shallow parts of the groove IllI s so that the rollersengage the surfaces of the counterbores IllZcb formed in the cups I02and the clutch is rotated. Upon the engagement of pin 96 at the end of arevolution of the clutch, the ring 91 is arrested and the momentum ofthe other parts of the clutch rotates the spider until lever I I0engages the notch I iOb so that the spider assumes the position of Fig.19, the rotation of cam I04, with respect to ring 81, before it isstopped by lever III], thereby placing a stress on spring I03, tocondition the same for the next cycle of operation.

The complete operation of the novel start-stop single revolution clutchmechanism of Figs. 17 to 23, inclusive, is as follows: Responding to aspacing line condition, the start-stop magnet SSM (Fig. 25) isdeenergized and the spring 95s moves the armature SSMA away from themagnet SSM and thereby rotates the stop arm 95 counterclockwise to theposition shown in Fig. 25a so that the pawl 95b is moved out of the pathof rotation of the pin 98 and pawl 95a is moved into the path ofrotation of this pin thereby stopping the clutch in the preliminary stopposition upon the engagement of pin 96 and pawl 95a (Figs. 3 and 25a).This is the position of the clutch when the system is deenergized and isnot in use.

Upon depression of the send-receive key SRKI (Fig. 4) at thetransmitting station A, for example, the line is energized, therebyenergizing start-stop magnet SSMI at this station, as will be explainedin detail later. The armature SSMA of SSMI is thereby attracted, asdiagrammatically shown in Fig. 4, so that arm 95 is rotatedcounterclockwise against the force of spring 95s to the position, asshown in Fig. 25b, and the pawl 95b is rotated into position tointercept the stop pin 96 so that the clutch is arrested in the normalstop position (Fig. 4).

Now, upon transmission of the normal start or spacing line condition.magnet SSMI is deenergized and the arm 95 is rotated counterclockwise tothe position, as shown in Fig. 250. As is clearly illustrated in thediagrammatic illustration of Fig. 250, this release will permit the pin96 to clear both of the pawls 95a and 95b and such release of pin 96permits ring 9! under control of spring I03 as described above, to movethe rollers into engagement with the cups to rotate clutch 94 untileither the pawl 95a is engaged, at the preliminary stop position beforethe completion of a full revolution, as shown in Fig. 3, or until pawl95b is engaged, as shown in Fig. 4, which occurs at the end of onecomplete revolution during normal operation because a stop or markingline condition is transmitted as the last signal, component of acomplete signal which stop signal energizes magnet SSMI to attractarmature SSMA to rotate arm 95 to the position, as shown in Fig. 25, anddiagrammatically illustrated only, in Fig. 4. Such engagement of pin 96stops the clutch and resets spring I03, as described above.

Rotation of the start-stop clutch produces rotation of the cam TC (Figs.3, 4, 6 and 1'7), cam I04 (Figs. 4 and 17), cam I09 (Figs. 4 and 17) andcam RC (Figs. 3, 4 and 1'7) and rotation of the cam TC (Figs. 3, 4, 6and 17) for example, sequentially operates the transmitting switches TIT6, inclusive, as previously explained. Upon receipt of the stop signalnear the end of one cycle of operation, the start-stop magnet isenergized to stop the clutch in the normal stop position, as previouslydescribed, thereby limiting the start-stop clutch mechanism 94 to asingle revolution only.

Mechanism for locally producing shift or carriage-return andsimultaneously producing a letters or figures shift signal or acarriage-return signal for remote control of these functions, will nowbe described. Referring to Fig. 26, a standard power cam II! for locallyproducing letters or figures shift, which shift cam is, a is well known,normally operative upon the downward stroke and also operative on theupward stroke,

is operatively connected for control thereby in the well known manner,to an extension II2a of an auxiliary key lever H2, in this instance,instead of being operative connected to the standard figs. key lever52F. Key levers H2 and 52F are mounted for rotation about thecylindrical rod element H3, in a manner well known in the art, the keylever 52F by means of its extension 55 controlling a single halfrevolution cam 62, as in Fig. 2.

The figs. key lever 52F is remotely controlled,

as diagrammatically illustrated in .Fig. 2, upon reception of a signal,by a seeker lever SL, and its connecting pin SLP extending into a keybar slot 558. The power shift cam, when operated by remote control orwhen manually operated through the digital operation of the figs. key5IF controls, in a normal manner, the shifting of the typewriter basketlocally, to figs. case, by operation of key lever H2 and consequentdownward stroke of extension II2a, while upon the upward stroke of leverH2 produced, by means L of interconnecting mechanism as will bepresently described, by depression of the letters key 5 IL, the basketis locally shifted to the letters case. The letters key lever 52L may beremotely controlled by means of a seeker lever, in the same manner asthe remote control of lever 52F, or it may be digitally operated. Theletters key lever 52L, by means of its extension 55, controls astandard, single half revolution power cam 62 having a slider actuatingroller 19 mounted on an extension of the support arm thereof, as in Fig.2.

A rocker lever H4 is pivotally mounted on the frame I I5 by means of a,pivot screw I I6. An inverted L-shaped lug III integral with the leftend of the lever I I4 engages in an opening II2b formed in the auxiliarykey lever I I2. The figs. key lever 5215, in its unoperated position,abuts the top of the rocker lever H4, and upon de pression, of the key5IF, will rotate the rocker lever counterclockwise. Likewise, theletters key lever 52L in its unoperated position, abuts the top of therocker lever and upon depression of this key lever it produces clockwiserotation of the rocker lever. A spring arm II8, attached to the frameH5, is provided with a circular, protruding element H9 which engages ineither an upper indentation I20 or a lower indentation I2I formed in theright hand end of the rocker lever I I4. When the rocker lever isrotated clockwise upon depression of the letters key 5I L, the protruding element II9 engages the top indentation I28 of lever II4, asshown in Fig. 26, to thereby hold the rocker lever in the extremeclockwise position. Likewise, when the lever I I4 is rotatedcounterclockwise by depression of the figs. key 5IF, the element H9engages the lower indentation I2I to hold the lever H4 in its extremecounterclockwise position.

The operation is as follows: The figs. key 5IF is first depressed andallowed to return to its normal position. Depression of the figs. keynot only releases its associated cam 62, in the well known manner, topermit roller 19 to operate the associated slider, as in Fig. 2, to setup the permutation code signal characteristic of figs. shift but alsorotates the rocking lever I I4 counterclockwise, and this lever is heldin the extreme counterclockwise position by means of sprin arm H8,element H9 and indentation I2I. Counterclockwise rotation of the rockerlever depresses the key lever I I2 by means of th inverted L- shaped lugI I1 integral with the lever I I4. Upon depression of lever H2, thislever remains down, releasing cam III for a half revolution only,whereby the type basket is locally shifted to the figs. case and willremain in that condition until the letters key is depressed.

' Upon depression and release of the letters key 5IL, on the other hand,not only is its associated cam 62 released to rotate a half revolution,so that its roller I9 will operate its associated slider, in a mannernow well understood, to set up the permutation code signalrepresentative of letters shift, but also the rocker lever H4 is, thistime, rotated clockwise to thereby raise lever I I2 to release cam I IIfor another half revolution whereby the type basket is locally shiftedto letters case.

Successive depressions of the figs. key or of the letters key willpermit repeat signals to be transmitted to the line but will not at allaffect the rocker lever I I4, so that the typewriter basket will locallyremain in either figs. case or letters case, depending upon Whether thefigs. key or letters key is being successively depressed.

There is also disclosed in Fig. 26, a novel carriage-return signalingand operating arrangement. It is to be noted, at this point, that in thestandard Electromatic typewriter, the carriage-return power cam is ofthe single lobe type, in contrast to the ordinary double lobe type, suchas is illustrated in Fig. 2. Upon actuation of the carriage-return key,the single lobe cam is locked in operative position until the typewritercarriage completely returns to the left hand margin. Due to the variableoperating time of the carriage-return cam, means mustbe provided toproduce a signal, corresponding to carriage-return, which will occupythe same time interval as all other signals.

Referring to Fig. 26, a carriage-return lever 520R is mounted forrotation about the rod H3 as a pivot, in the well known manner. Anauxiliary lever I22 is likewise mounted for rotation about rod II3. Agenerally U-shaped connecting link I23 is pivotally mounted in a bracketI24 fastened to a part of the frame, by any well known means. One end ofthe link I23 engages in an opening formed in the key lever 520R whilethe opposite end of the link I23 engages in an opening formed in thelever I22. The carriagereturn lever 52CR controls the usual single lobecam (not shown) producing carriage-return locally. The lever I22,controls an ordinary twolobe power cam (not shown) in the same mannergenerally, as lever 52L, for example.

The operation is as follows: Upon depression of the carriage-return keyICR, a single lobe power cam is released and the carriage at the localmachine is returned to its left hand margin.

Simultaneously, upon depression of the key 5ICR, the lever 520R isdepressed and the link I23 operated thereby depresses lever I22 therebyreleasing the ordinary two-lobe power cam such as 62. associatedtherewith, to set up the carriage-return signal permutation so thatconsequently the machine at the remote station is controlled by thereceived signal to operate the carriage-return lever at Said remotestation and thereby produce a return of the carriage at the remotestation, to its left hand margin. By utilizing the combination of lever52GB and lever I22 with the respective cams, as controlled by theselevers, the function of carriage-return is produced locally, in theusual manner, and a carriage-return signal, of equal duration to allother character or function representing signals, is transmitted to aremote station.

The details of the keyboard lock-out or speed lock mechanism whichcomprise a part of the novel break-in means is disclosed in Fig. 5. Thiskeyboard lock-out is of the type as disclosed in the copendingapplication of Henry L. Tholstrup, Serial No. 298,005, filed October 5,1939, now Patent 2,255,030, granted Sept. 2, 1941.

Referring to Fig. 5, the lock-out means are seen as comprising a combI25 of the typewriter provided with a lock-out mechanism comprising aplurality of rollers I 26, mounted in a roller guide I27, these rollersbeing of such diameter and so spaced that only one key lever or thelock-out lever only, can be depressed at any one time. A lock-out leverI 28, similar to the ordinary key lever of a typewriter, is mounted, bymeans of rod II3, for oscillation in a vertical plane about said rod asa pivot. A spring I29, attached by a hook I30 to the lever I28 at oneend thereof and fastened to the frame of the typewriter by means such asI3I at the other end thereof, biases the lever against the top of aguide slot I3I in the comb I25.

A coil spring I32 having one end I33 thereof threaded through an openingI34 in lever I28, is connected at its other end to a lug I35 integralwith the top of plunger I36 comprising the armature of a "lock-out orlatch magnet LM (see also Fig. 4) mounted in the U-shaped base I31.

The energization of latch magnet LM is controlled by the novel break-insystem which will be described in detail later.

The operation of the look-out is as follows: Upon energization of themagnet LM, the plunger CPI or armature I35 is drawn downwardly, asviewed in Fig. 5, applying a force to the coil spring I32 whereby thelook-out lever I23 is oscillated, about the rod I I3as a pivot, againstthe force of bias spring I29 and thereupon lever I28 is pulleddownwardly to the bottom of the guide slot I3I and between a pair of therollers I26 whereby the spacing between the rollers is so decreased,that no key lever of the typewriter can now enter therebetween untillever I28 is retracted by the spring I29 upon 'deenergization of magnetLM. The utilization of the lock-out means in combination with 'a novelbreak-in system, will be described in detail later.

Receiving mechanism The receiving mechanisms and related circuits areillustrated diagrammatically only, in Figs. 3 and-4, and it is to beparticularly noted that such circuits and such mechanisms are providedat both the sending and receiving machines. It is also to beparticularly noted, as described above, that elements of thetransmitting mechanism and 0f the receiving mechanism at any one stationare both mounted upon a single shaft 83 for operation by the same clutch94, as illustrated diagrammatically in Figs. 3 and 4. The receivingmechanism comprises a receive cam RC similar in construction to thetransmission cam TC (Fig. 6) and mounted on the same shaft 83 as thetransmitting cam, as diagrammatically illustrated in Figs. 3 and 4. Thisreceiving cam controls a plurality of switches RI, R2, R3, R4, R5 andR6, each including at least a pair of switch elementsa and b, andsimilar to the transmission switches TI to T6, inclusive, as .illustrated in Fig. 6. As is seen from Figs. 3 and 4, the contacts comprisingthe individual switches R1 to R5, inclusive, are in series with a powersource; through the contacts of the send-receive relay, the permutationslide bar magnets MI to M5, inclusive, and the armature of line relayLR2, for example, and printing magnet PM; and switch R3 is similarly inseries with the startstop magnet solenoid SSMZ; whereby the switches RIto R5, sequentially and selectively control the current through thepermutation slide bar magnets and switch R6 controls the energization ofSSMZ in accordance with the characteristics of the received code signalpermutation elements, respectively. Since the receive cam RC .iscontrolled by the same clutch 94 as the transmitting cam TC, the twocams at any one machine are rotated in unison. Means are provided, asdescribed in detail later, for rendering the receive cam and itsassociated switches, at the sending station, ineiTective duringtransmission, while the receive cam, at the receiving station, isreleased for rotation in step with the transmitter cam at the sendingstation, all as described later.

Referring to Figs. 7 to 16, inclusive, the con struction, arrangementand manner of operation of the novel signal storage mechanism, includingan overlap arrangement, will now be described in detail. This signalstorage mechanism is of the mechanical storage type wherein thetranslator or permutation slide bars are selectively positioned, inaccordance with the character of the respective signal elementscomprising a received line code signal permutation, to align a certainseries of notches in the respective bars, so that one seeker lever only,will be operated, to thereby operate its associated key lever uponoperation of the drop or print bar, when the latter is actuated inresponse to a timed local impulse from print segment PS of the receivedistributor, The translator is mounted in the typewriter directlybeneath the key levers and above the permutation unit.

Referring to Figs. 11, 12 and 13, the translator unit is shown ascomprising a plurality of five permutation slide bars I 38, separated byelongated rollers I39 (Figs. 12 and 13) mounted in openings I40 in therespective slide bars. The bars are slidably mounted on cross membersI4I. A pair of brackets I42, attached to cross members I4I by screwsI43, serve to securely fasten the translator unit in place beneath thekey levers. Support members I44 and I45 maintain the bars in properalignment and prevent lateral separation of the bars. The permutationslide bars are provided with notches arranged in accordance with theBaudot code, so that, upon relative longitudinal arrangement of thebars, selectively in accordance with the elements of a received codesignal permutation, only one series of slots will be aligned for any onesignal permutation received. A stop member I46 fastened by screws I41 toone of the cross members I4I cooperates with an extension I38a on eachpermutation bar to limit the longitudinal movement of the bar, when itis released by the permutation bar magnet corresponding thereto. A coilspring I48, is provided for each slide bar, having a hook I 4811 at oneend attached to the corresponding bar by insertion into an opening I38bin the bar and the opposite end is maintained in position by a pin I49passing through an eye I481), the pin abutting an angle member I50attached to one of the cross members MI by screws I-I (Fig. 11). Thepermutation slide bars are "positioned in their extreme left handposition, by means of the restore magnet RM (Fig. controlling itsarmature RMA carrying the restore arm I52 extending into each of thenotches I380 formed in the permutation slide bars. Upon energization ofthe restore magnet, as will be described in detail later, its armatureis attracted and the restore arm I52 engaging a side of a notch I380,moves the slide bars against the force of their bias springs I43, to theleft, to their extreme left hand position, as illustrated in Fig. 11. Aseries of permutation slide bar magnets MI to M5, inclusive, one foreach slide bar respectively, is provided and their armatures providedwith latches maintain the slide bars in the extreme left hand position,as described presently, when the magnets are deenergized, and uponenergization of the magnets by received signal elements they selectivelyrelease the slide bars from said position, in accordance with theparticular code signal permutation received. Each of the translatormagnets, such as M4 of Fig. 11, for example, is mounted on a frame I 53attached to the front plate I 54 by means of screws I55, which plate inturn is attached to the cross members MI by screws I55. Each magnet isprovided with an armature I-5'I, mounted for oscillation about a pair ofpivot points I53 carried by frame I53. Armature I5! is provided with alatch member I5lI (Figs. 12 and 14) at one end and is urged to theposition as illustrated in Fig. 11 against a stop (not shown) by meansof a spring bias member I59 whose biasing force is adjusted by means ofan adjustable screw I60. When the restore magnet RM has been energizedto restore the slide bars I38 to their extreme left hand position, asillustrated in Figs. 11 and 12, the latches I5II, when magnets MI to M5are deenergized, abut a shoulder I38d, on each slide bar I38, to holdthe bar in position against the force of its related spring I48. Uponselective energization of any of the permutation slide bar magnets, inaccordance with the respective received code permutation elements, theenergized magnet,

. such as M4, for example, attracts its armature I51 to therebydisengage the latch 15' from the shoulders I38d (Fig. 12) whereupon thespring I48 pulls the slide bar to the right, to the position asillustrated in Figs. 14 and 15. The particular permutation of slidebars, so released, determines the particular array of notches which isaligned, which in turn determines the particular seeker lever that canenter the aligned notches, which seeker lever, upon operation of theprint bar, depresses its connected key lever to operate the same, asillustrated diagrammatically in Fig. 2.

As illustrated in Fig. 16, certain of the permutation slide bar magnets,such as MI and M2, for example, may be provided With novel means wherebythe slide bar magnet is maintained energized long enough for the restoremagnet to operate fully, which latter operation may not occur until thefirst and second selecting code signal elements of the next succeedingcharacter signal have been transmitted over the line and received at thereceive station, whereby the full signal transmitting capacity of thesystem may be utilized.

As is seen in Fig. 16, a permutation slide bar magnet such as MI or M2,for example, comprises a core I6I upon which is wound a low resistancecoil I62 of comparatively few turns concentrated at the armature end ofthe core. In series with coil I62 is a high resistance winding I63 ofseveral thousand turns occupying the heel end of the core and shunted bya storing condenser I64. When the local pulse, corresponding to areceived code signal permutation element, is applied to the winding ofthe corresponding magnet, a rush of current flows through the lowresistance winding I62 into the storing condenser I64, which, because ofits large capacity, ofiers comparatively little impedance to such rushof current and hence the current magnetizes the core I62 at the armatureend to attract the armature I51 so that the latch I5TI assumes theposition as illustrated in Fig. 14. The electrical energy thus stored incondenser I64, combined with that stored in the coil, maintains the coreenergized after decay of the local pulse, to thereby hold the armaturein the posi-- tion shown in Fig. 14, for a time interval determined bythe electrical constants of the condenser and coil. The armatures I51 ofmagnets MI and M2, are thus maintained in the position as illustrated inFig. 14, until the restore magnet RM has operated its restore arm I52(Fig. 15) to restore all of the permutation slide bars to the positionas illustrated in Figs. 11 and 12, and also until the restore magnet RMhas been deenergized, so that the slide bars I38, corresponding tomagnets MI and M2, respectively, are released and moved to the right bytheir springs I48, so that the respective shoulders I33cl are in theposition as illustrated in Fig. 15, whereupon the magnets MI and M2 mayrelease their armatures and latches 15', without interfering with thesetting of the permutation bars in accordance with the first twoselecting components of a succeeding received code signal permutation.

Referring to Figs. 8 and 9, there is diagrammatically illustratedtherein, a drop or printing bar I65 and its associated operatingmechanism. Print or drop bar I65 is supported for movement in a planeparallel to the plane of the permuta-

